i want use fuse 1A in my power supply circuit.i have never used a fuse before.so can anyone tell me how to use it and how should i place it in the circuit?
Fuse should be placed first in line of the hot legclosest to the power source.
Fusing and disconnecting means, should always be placed on the UNGROUNDED CONDUCTORS. I.e. any circuit that will operate at a significant voltage above or below ground. You do not fuse your grounded current-carrying conductors (aka neutrals), because these are usually connected to ground at the source, in some form or another. If your circuit is completely ungrounded, as in, all live wires float either above or below ground, with no exact connection to ground, you fuse all current-carrying conductors, treating them all as live wires. For a single phase transformer, you only need to fuse it on one side. Because any fault current will be transferred winding-to-winding directly. For other configurations of transformers, where the topology doesn't guarantee that it faults occur in a winding-to-winding manner, you may need to fuse it on both the primary and the secondary. It is recommended that you use a TOUCH-SAFE fuseholder, to store the fuse. You can directly connect the wires to the fuse holder, and then you can pop the fuse in it, when you are ready to power the circuit on. Do not disconnect any fuses under a current-carrying load. Make sure you shut it off at a device rated for disconnecting means, at that voltage.
I'd use two. One in the primary of the transformer, in series with the hot lead. If you don't know which is hot, use two, one in series with each lead. Probably 1/4 amp would do. The one in the secondary, you already have marked on the schematic. Make sure it is a slo-blo type (slow blow) otherwise when the supply is first turned on, the charging current into C1 will pop it. Note that the overvoltage circuit depends on the fuse. edit: should i connect the wires to it? huh? how else do you put it into the circuit. You have little chance of ever getting this working, given this. Just as a clue: all components have terminals, 2,3,4, possibly more. You connect them into the circuit by connecting wires to each one.
